1. Field of the Invention
The present invention relates to a master electrode and a method of forming the master electrode. The master electrode is useable in an etching or plating method as described in a copending Swedish patent application No. 0502538-2 filed concurrently herewith and entitled “METHOD OF FORMING A MULTILAYER STRUCTURE”. The content of this patent specification is incorporated herein by reference. The master electrode is suitable for enabling production of applications involving micro and nano structures in single or multiple layers. The master electrode is useful for fabrication of PWB (printed wiring boards), PCB (printed circuit boards), MEMS (micro electro mechanical systems), IC (integrated circuit) interconnects, above IC interconnects, sensors, flat panel displays, magnetic and optical storage devices, solar cells and other electronic devices. Different types of structures in conductive polymers, structures in semiconductors, structures in metals, and others are possible to produce using this master electrode. Even 3D-structures in silicon, such as by using formation of porous silicon, are possible to produce.
2. Description of Related Art
WO 02/103085 relates to an electrochemical pattern replication method, ECPR, and a construction of a conductive master electrode for production of appliances involving micro and nano structures. An etching or plating pattern, which is defined by a master electrode, is replicated on an electrically conductive material, a substrate. The master electrode is put in close contact with the substrate and the etching/plating pattern is directly transferred onto the substrate by using a contact etching/plating process. The contact etching/plating process is performed in local etching/plating cells, which are formed in closed or open cavities between the master electrode and the substrate.
The master electrode is used for cooperation with a substrate, onto which a structure is to be built. The master electrode forms at least one, normally a plurality of electrochemical cells in which etching or plating takes place.
The master electrode may be made of a durable material, since the master electrode should be used for a plurality of processes of etching or plating.
A problem is that the master electrode is to be arranged in a carefully adjusted position on the substrate in order for the pattern to be aligned with previous structures on the substrate.
A further problem is that the master electrode is to be arranged in close proximity of a substrate when said substrate comprises topography.
A yet further problem is that the etching rate or plating rate may be higher in the electrochemical cells located closer to the contact area of the seed layer, such as in the perimeter, than in other areas.
Further problems are mentioned below.
While the systems and methods of the present application is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present application.